ErrorProvider : ErrorProvider : GUI Windows Forms C# Examples

    
using  System;
using  System.Collections.Generic;
using  System.ComponentModel;
using  System.Data;
using  System.Drawing;
using  System.Text;
using  System.Windows.Forms;

public  partial  class  Form1  :  Form
{
        public  Form1()
        {
                InitializeComponent();
        }

        private  void  numberBox_Validating(object  sender,  CancelEventArgs  e)
        {
                try
                {
                        int  numberEntered  =  int.Parse(numberBox.Text);
                        if  (numberEntered  <  1  ||  numberEntered  >  10)
                        {
                                e.Cancel  =  true;
                                errorProvider1.SetError(numberBox,  "You  must  enter  a  number  between  1  and  10");
                        }
                }
                catch  (FormatException)
                {
                        e.Cancel  =  true;
                        errorProvider1.SetError(numberBox,  "You  need  to  enter  a  whole  number");
                }
        }

        private  void  numberBox_Validated(object  sender,  EventArgs  e)
        {
                MessageBox.Show("Well  done,  you  managed  to  enter  a  valid  number");
        }

        private  void  okButton_Click(object  sender,  EventArgs  e)
        {
                this.Close();
        }

        private  void  numberBox_TextChanged(object  sender,  EventArgs  e)
        {
                MessageBox.Show("text  changed");
        }

}
partial  class  Form1
{
        private  void  InitializeComponent()
        {
                System.ComponentModel.Container  components  =  new  System.ComponentModel.Container();
                this.numberBox  =  new  System.Windows.Forms.TextBox();
                this.label1  =  new  System.Windows.Forms.Label();
                this.okButton  =  new  System.Windows.Forms.Button();
                this.errorProvider1  =  new  System.Windows.Forms.ErrorProvider(components);
                ((System.ComponentModel.ISupportInitialize)(this.errorProvider1)).BeginInit();
                this.SuspendLayout();
                //  
                //  numberBox
                //  
                this.numberBox.Location  =  new  System.Drawing.Point(190,  12);
                this.numberBox.Name  =  "numberBox";
                this.numberBox.Size  =  new  System.Drawing.Size(44,  20);
                this.numberBox.TabIndex  =  0;
                this.numberBox.Validated  +=  new  System.EventHandler(this.numberBox_Validated);
                this.numberBox.Validating  +=  new  System.ComponentModel.CancelEventHandler(this.numberBox_Validating);
                this.numberBox.TextChanged  +=  new  System.EventHandler(this.numberBox_TextChanged);
                //  
                //  label1
                //  
                this.label1.AutoSize  =  true;
                this.label1.Location  =  new  System.Drawing.Point(12,  15);
                this.label1.Name  =  "label1";
                this.label1.Size  =  new  System.Drawing.Size(164,  13);
                this.label1.TabIndex  =  1;
                this.label1.Text  =  "Enter  a  number  between  1  and  10";
                //  
                //  okButton
                //  
                this.okButton.Location  =  new  System.Drawing.Point(251,  9);
                this.okButton.Name  =  "okButton";
                this.okButton.Size  =  new  System.Drawing.Size(75,  23);
                this.okButton.TabIndex  =  2;
                this.okButton.Text  =  "OK";
                this.okButton.Click  +=  new  System.EventHandler(this.okButton_Click);
                //  
                //  errorProvider1
                //  
                this.errorProvider1.ContainerControl  =  this;
                //  
                //  Form1
                //  
                this.AutoScaleDimensions  =  new  System.Drawing.SizeF(6F,  13F);
                this.AutoScaleMode  =  System.Windows.Forms.AutoScaleMode.Font;
                this.ClientSize  =  new  System.Drawing.Size(340,  47);
                this.Controls.Add(this.okButton);
                this.Controls.Add(this.label1);
                this.Controls.Add(this.numberBox);
                this.Name  =  "Form1";
                this.Text  =  "Form1";
                ((System.ComponentModel.ISupportInitialize)(this.errorProvider1)).EndInit();
                this.ResumeLayout(false);
                this.PerformLayout();

        }

        private  System.Windows.Forms.TextBox  numberBox;
        private  System.Windows.Forms.Label  label1;
        private  System.Windows.Forms.Button  okButton;
        private  System.Windows.Forms.ErrorProvider  errorProvider1;
}
public  class  ErrorProviderTextBox
{
        [STAThread]
        static  void  Main()
        {
                Application.EnableVisualStyles();
                Application.Run(new  Form1());
        }
}